The Carâfollowing model plays a major role in the study of traffic flow theories and traffic simulation. Carâfollowing behaviours can be regarded as a game process between the desired driving state and the real traffic state. By defining the expected carâfollowing state, this paper expresses the game process with a graph attention neural network, and developed the GATCF carâfollowing model. Different from other models that apply time series information as input, GATCF only needs instantaneous information as feature input. Two simulation cases, trajectory sequence prediction and multiâvehicle simulation, are performed with the Iâ80 data in the NGSIM project. Compared with other carâfollowing models such as Gipps model, Optimal Velocity model, and Intelligent Driver model, the GATCF model developed in this paper shows higher accuracy and stability.